This present disclosure relates to a microparticle analysis apparatus and a microparticle analysis method. Specifically, it relates to a technique that can enhance the detection accuracy of forward-scattered light generated from microparticles.
In the related art, there has been used a microparticle analysis apparatus that irradiates light to a microparticle flowing in a flow cell or a channel formed in a microchip and detects the scattered light generated from the microparticle and the fluorescence generated from the microparticle or a fluorescent material labeled to the microparticle. This microparticle analysis apparatus measures the optical property of the microparticle that is an analysis object by detecting the scattered light and fluorescence generated from the microparticle and the like. Moreover, there has been used an apparatus (which may be referred to as “flow cytometer” or “cell sorter”) adopting a fractionation-system configuration that sorts and recovers only microparticles having a given characteristic.
In the field of microparticle analysis apparatuses, various configurations have been suggested in order to improve the detection accuracy and analytical precision of the fluorescence and scattered light generated from a microparticle that is an analysis target. For example, JP 2012-26837A suggests a microparticle measurement apparatus having an optical filter including a transmission region of fluorescence and a transmission region of scattered light, on an optical path that guides the light generated from a microparticle to a light detector, in order to acquire backscattered light and fluorescence more efficiently. Moreover, JP 2012-47464A describes a microparticle measurement apparatus including a light focusing unit that focuses straight irradiated light without being scattered and scattering light scattered by a microparticle in a light receiving element divided into a plurality of regions, in order to enable a highly accurate measurement to be performed. This JP 2012-47464A suggests using an optical filter having a blocking region of irradiated light and a transmission region of scattered light, as a light focusing unit in the microparticle measurement apparatus.